Electric switch.



H. R. SCHULTZ.

I ELECTRIC SWITCH. APPLICATION FILED JULY22. 1910.

4 1,175,308. w Patented Mar. 14,1916.

5 SHEETS-SHEET 1.

Rig. 4.

H m I AT'TORNEY THE COLUMBIA PLANOGRAPH co., \YASHXNGTON. D. c.

H. R. SCHULTZ.

ELECTRIC SWITCH.

APPLlCATlON FILED JULY 22. 1910.

Patented Mar. 14, 1916.

5 SHEETSSHEET 2.

"IllllulIIIIIIIIIIIIIIIIM THE COLUMBIA PLANOGRAPH C0., WASHINGTON, n. c

H. R. SCHULTZ.

ELECTRIC SWITCH.

APPLICATION FILED JULY 22, I910.

5 SHEETS-SHEET 3.

WITNESSES: 4 21 v R 41 44- ATTORNEY THE COLUMBIA PLANOGRAPH C0,, \VASEIIR'GTON n. c.

H. R. SCHULTZ.

ELECTRIC SWITCH.

APPUCATION FILED JULY 22. 1910.

1,175,308. Patented Mar. 14, 1916.

5 SHEETS-SHEET 4.

WITNESSES: I E T R Wm WM ATITORNEY THE COLUMBIA PLANOGRAPH 120.. WASHINGTON. D. c.

H. R. SCHULTZ.

ELECTRIC SWITCH.

APPLICATION FILED JULYZZ, 1910.

1,175,308. Patented Mar. 14, 1916.

5 SHEETS-SHEET 5.

Big. 6.

WlTNESSES: I INgE ZTOR Ai'TURNEY THE COLUMBIA PLANOGRAPH co., WASHINGTON, D. c.

UNITED STATES PATENT OFFICE.

HJ'ALMAR RUDMAN SCHULTZ, OF TRAFFORD PARK, MANCHESTER, ENGLAND, ASSIGNOR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

ELECTRIC SWITCH.

Application filed July 22, 1910.

To all whom it may concern Be it known that I, HJALMAR RUDMIAN SCHULTZ, a subject of the King of Sweden, and a resident of Trafford Park, Manchester, England, have invented a new and useful Improvement in Electric Switches, of which the following is a specification.

My invention relates to electric switches and particularly to such switches as are adapted to be manually or automatically opened when the voltage of the circuit to which they are connected falls below a predetermined limit or when a predetermined excessive current passes through them.

My invention has for its object to provide a switch of the above character which shall be simple and cheap to manufacture, reliable in operation and, as far as possible, proof against injury from unskilled operation or interference.

In order that my invention may be clearly understood, a preferred embodiment of the same will now be described with reference to the accompanying drawings, of which:

Figures 1 and 2 are views in front and side elevation, respectively, but partly sectional, of a switch constructed in accordance with my invention. Fig. 3 is a plan view on the line IIIIII of Figs. 1 and 2. Fig. 4 is a diagrammatic view showing the circuit connections of the various elements of the switch and its control apparatus. Figs. 5 and 6 are views in side elevation illustrating a preferred means for connecting the switch to a. terminal box into which the circuits to be controlled by the switch are led, the switch being shown in its operative position in Fig. 5 and as partly withdrawn from the terminal box in Fig. 6.

Referring now to Figs. 1, 2 and 3, the switch 1, which is adapted to control a three-phase alternating current circuit, has a frame or casing 2 within which a shaft 3 is mounted horizontally in suitable bearings. Three pairs of stationary contact terminals 4 and 5 are adapted to be engaged by corresponding bridging contact members 6 which are mounted upon an insulating bar 7. The bar 7 is suspended, by means of insulating links 8, from crank arms 9 which are attached to the shaft 3, said shaft being provided with an external handle or lever 10 by means of which it may be given a rotative movement to raise the insulating bar 7 and the bridging contact members 6 Specification of Letters Patent.

Patented Mar. 14, 1916.

Serial No. 573,210.

into engagement with the stationary contact terminals 4 and 5. In order to retain the switch in its closed position, one of the crank arms 9 is provided with an extension 57 which is adapted to engage the forked end of a trigger 11, the pivot 12 of which projects from the side of the casing 2. The upper side of the other end 13 of the trigger 11 is adapted to be engaged by a roller 14 with which one end of the vertical arm 15 of a locking lever 16 is provided. The lever 16 is pivoted at 17 to the switch casing 2 and is provided with a counter weight 18 at one end of a horizontal arm thereof which causes the roller 14 to pass over the end 13 of the trigger 11 when the latter is moved into a position corresponding to the closed position of the switch, the roller 14 of the locking lever 16 thus serving to retain the trigger lever 11 and, consequently, the movable member of the switch, in closed position.

In order to open the switch, the locking lever 16 is provided with an arm 19 that projects substantially at right angles to the vertical arm 15 and is moved downwardly to release the trigger 11 by means of the core 20 of a solenoid 21 which constitutes a no-voltage release coil of theswitch. The core.20 is maintained out of engagement with the arm 19 of the locking lever 16 so long as the solenoid 21 is energized to a predetermined degree. A further means. for actuating the locking lever 16 to permit the switch to open comprises a bell crank lever 22 that is pivoted at 23 upon the switch casing 2 and has a vertical arm 24 to engage a pin or projection 25 on the arm 15 of the locking lever 16 and move the arm to disengage the end of the trigger 11 from the roller 14. The horizontal arm 26 of the bell crank lever 22 is arranged to be moved by the arm 27 of a rocking bar 28 which is pivoted at 29 and 30 to the casing 2 and is provided with an external control handle 31 for operating it manually, when desired. The control handle 31 may be set in any one of three positions, Auto, Off and Non-auto, as indicated in Fig. 2, and a U-shaped spring 32 is provided to embrace a flattened portion of the rocking bar 28 to tend to maintain the said bar in the position marked Auto.

The overload tripping device of the switch is indicated at 34 and comprises solenoids 35 within which cores 36 are adapted to move, the cores 36 being provided with rods 37, to the lower ends of which disks 38 are attached. The rods 37 project through slots 33 in the rocking bar 28 so that, when one or more of the solenoids 36 is energized to a predetermined degree, one or more of the cores 36 will be moved upward and will bring the disk 38 into engagement with the rocking bar 28 and move it toward the Off position to permit the switch to open, in the manner already described.

The switch is also provided with an ammeter which is indicated at 39 and the actuating windings of which are connected in series with one of the circuits to be controlled, the connections of the no-voltage coils 21, the overload coils 35 and the ammeter 39 being indicated diagrammatically in Fig. 4. The switch, as indicated in Figs. 1., 2 and 3, is provided with a terminal box 40 into which project the three pairs of conductors 11, 12 that correspond to the three phases of the circuits to be controlled by the switch.

The operation of the switch is as follows: Assuming the switch to be in its open position, the shaft 3 is given a rotative movement by moving the handle 10 in an upward direction to raise the movable member of the switchinto its closed position, in which the movable contact members 6 are in engagement with the respective stationary contact terminals 41 and 5. The rotative movement of the shaft 3 causes the end of the extension 57 to move upward and carry with it the forked end of the trigger 11 and cause a corresponding downward movement of the arm 13 of said trigger until the roller 14 is able to pass over its end, under the action of the counter weight 18, to retain the switch in its closed position. In the event of the voltage of the circuit to which the switch is connected falling below a predetermined amount, the core 20 of the no-voltage coil 21 will descend upon the arm 19 and move the locking lever 16, against the action of the counter weight 18, until the end of the arm 13 of the trigger 11 is released from the roller 14:, whereupon the movable member of theswitch will return to its open position, under the action of gravity. The switch may also be opened, as follows: When the rocking bar 28'is actuated to the Off position, either manually by the movement of the control handle 31, or automatically by the upward movement of any of the cores 36 of the overload tripping devices 34, the lever 27 depresses the arm 26 of the bell crank lever 22 until the other arm 24. of the said lever engages the pin 25 on the arm 15 of thelockinglever 16 and causes the said arm to move the roller 14 out of engagement with the end of the trigger 11 and thus permit the switch to open, as described above.

It will be understood that the U-shaped spring tends to maintain the rocking bar 28 in the position corresponding to the Auto position of the control handle 31, so that, unless the said handle be manually held in the Non-auto position, the switch will be automatically opened. upon the occurrence of an overload. The switch may, however, be rendered non-automatic. if desired, by holding the control handle 31 in the Non-auto position, either manually or by means of a suitable locking device.

The switch is preferably arranged to be electrically connected to the conductors of the circuit which it controls by spring clips or sockets which are attached to the conductors and into which contact pieces or plugs are inserted, the said Contact pieces or plugs being attached to the switch contacts and projecting beyond the switch casing. A preferred form of construction of this kind is illustrated in Figs. 5 and 6 in which one pair of circuit conductors -11 and Hare connected to spring clips orsockets a3 and 1-1 that are mounted upon the frame of the terminal box but are insulated therefrom. The stationary contact terminals 4; and 5 of the switch are connected to corresponding plugs or contact pieces 15 and 46 which project horizontally beyond the switch casing 2. The switch 1, when connected to the terminal box, is supported by means of horizontal guide rods 1-7 which are rigidly attached to the casing 2 and are adapted to slide within horizontal tubes 18 in the frame of the terminal box 10. By this means, the switch 1 may be withdrawn from the terminal box 1O sufficiently to disconnect the plugs 45 and 46 from the clips 13 and 14: so

, that the switch contact terminals are no longer connected to thecircuit conductors. 7

When in. this position, the switch is still supported by the guide rods 17 and inspection or repairs can be readily effected. The

switch 1 may be secured to the terminal box 510 by bolts -19 and a padlock 50, and a door 51 may be provided for closing the front of the terminal box 4-0 when the switch is entirely removed therefrom. In order to prevent the withdrawal of the switch, as above described, when the switch mechanism is in its closed position, the terminal box is provided with a horizontal bar 52 having a notch 53 with which a projection 54 on the handle 10 is adapted to engage when the latter is in its closed position, as shown in Fig. 5. It will be readily understood that, under these conditions, the switch 1 cannot be withdrawn from the terminal box 40 into the position shown in Fig. 6 so long as the handle 10 of the switch is in its closed position. In order to withdraw the switch into the position shown in Fig. 6, it is therefore necessary to move the handle 10 into its open position in which the projection is out of engagement with the notch 53 and, during the withdrawal of the switch, the handle 10 is prevented from bein moved to its closed position by reason of the projection 5e engagingwith the upper edge of the bar 52. lVhen the switch is in the position shown in Fig. 6, however, the switch handle 10 can be freely operated, a Second notch 61 being provided in the bar 52 to admit the proyection 5d. The bar 52 is also provided with spring catches '58 to engage the respective sides of the pro jection 5- on the controller handle 10. When the switch is withdrawn from the terminal box sL-O, it cannot be returned to its original position until the spring catch is manually retracted, and complete removal of the switch 1 cannot be effected until the catch 58 is similarly retracted.

A hood or cap 56 is provided for inclosing the upper portion of the apparatus comprising the overload tripping device. and the ammeter and the switch contacts are preferably located in an oil tank 59 which is attached to the base of the switch casing 2. The removal of either the hood 56 or the tank 59, when the switch is attached to the terminal box so, is prevented by a stirrup 60 which is attached to the terminal box 40 and closes the said hood and tank when the switch is connected to the terminals in the box 40.

The structural details of the switch may evidently be varied from those above described without exceeding the scope of the invention.

I claim as my invention:

1. In a switch for electric circuits, the combination with movable and stationary contact terminals and overload and no-voltage tripping coils, of an operating mechanism for effecting an engagement of the movable and stationary contact terminals, a trigger for normally maintaining the said contact terminals in efiective engagement, a pivotally mounted lever for locking the said trigger, actuating means independent of the said operating mechanism and interposed between the overload coil and the locking lever, and means for changing the relative position of the actuating means with respect to the overload coil to place it in automatically operative or in inoperative relation to the said trip coil or to manually trip the said switch.

In a circuit interrupter, the combination with stationary and movable contact members, an operating mechanism therefor. and means for restraining said mechanism. of electromagnetic tripping means for releasing the restraining means, and means iuoependent of the said operating mechanism and interposed between the electroof a plurality of load-responsive devices severally adapted to release said restraining means, and an adjustable member adapted to be actuated manually or by any of said loadresponsive devices to effectthe release of said restraining means or to prevent the electro-responsive means from ef fecting a release of said restraining means.

at. A circuit interrupter comprising a containing casing, a plurality of stationary and movable contact members, an operating mechanism therefor disposed within said casing, an operating handle exterior to said casing, a latch for said mechanism, a plurality of over-load trip coils, and a device independent of said mechanism and having a handle exterior to said casing for manually tripping said interrupter for adapting the over-load trip coils to automatically trip the same or for preventing the automatic tripping of the same.

A. circuit interrupter comprising a containing casing, a plurality of stationary and movable contact members, an operating mechanism therefor disposed within said casing, an operating handle exterior to said casing, a latch for said mechanism, a plurality of overload trip coils adapted to effeet the release of said latch under predetermined conditions, and a device independent of said operating mechanism and adapted to be moved into a plurality of distinctoperating positions for manually releasing said latch and for effecting automatic operation of the latch or for preventing automatic operation of the same.

6. In a circuit interrupter, the combination with stationary and movable contact members, an operating mechanism for the movable contact members. and a latching device for holding the mechanism in its closed position, of a plurality of overload trip coils for effecting the release of said latch, and a manually adjustable member for effecting the operation of the inter rupter manually or automatically or for preventing automatic operation thereof.

'7. In a circuit interrupter, the combination with cooperating contact members, an operating mechanism therefor, and a latch for normally restraining said mechanism in its closed osition, of a lever for locking said latch. an auxiliary lever cooperating with said locking lever, and an actuating mem ber adapted to engage said auxiliary lever and to occupy a plurality of distinct operating positions for manually tripping or automatically tripping the interrupter or for preventing the automatic tripping thereof on overloads.

8. In a circuit interrupter, the combination with cooperating contact members, an operating mechanism therefor and a latch for manually restraining the said mecha nism, of a biased pivotally mounted lever for locking the said latch, a no-voltage trip coil for actuating the said lever, an auxiliary lever cooperating with the locking lever, a plurality of overload trip coils, an adjustable member interposed between the overload trip coils and the auxiliary lever, and means for manually adjusting the adjustable member to occupy a plurality of distinct operating positions for rendering it operative or inoperative with respect to the overload trip coils or to manually trip the interrupter.

9. In a circuit interrupter, the combination with stationary and movable contact members, an operating mechanism therefor, a latch for normally restraining said mechanism, a plurality of overload tripping coils, a lever interposed between said tripping coils and said latch, means for manually actuating said lever to place it in automatically operative or in inoperative relati on to the said tripping coils or to manually trip said latch.

10. The combination with a circuit breaker, of means for tripping the circuit HJALMAR RUDMAN SCHULTZ. WVitnesses J. S. Prion, Gno. PIMUs.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

